Bending apparatus



June 29, 1965 D. M. RIPPE 3,191,419

BENDING APPARATUS Filed May l0, 1962 7 Sheets-Sheet l June 29, 1965 D. M. RIPPE 3,191,419

BENDING APPARATUS Filed May l0, 1962 '7 Sheets-Sheet 2 June 29, 1965 D. M. RIPPE BENDING APPARATUS '7 Sheets-Sheet 3 Filed May 10, 1962 June 29, 1965 D. M. RIPPE 3,191,419

BENDING APPARATUS Filed May lO, 1962 '7 Sheets-Sheet 4 June 29, 1965 D. M. RIPPE 3,191,419

BENDING APPARATUS Filed May lO, 1962 '7 Sheets-Sheet 5 June 29, 1965 D. M. RIPPE 3,191,419

BENDING APPARATUS Filed May lO, 1962 7 Sheets-Sheet 6 June 29, 1965 D. M. RIPPE 3,191,419

BENDING APPARATUS Filed May 10, 1962 7 Sheets-Sheet '7 FIG. I2.

United States Patent() 3,191,419 BENDING APPARATUS Dondeville M. Rippe, Webster Groves, Mo., assignor to Dondeville Products Co., Inc., Webster, Mo., a corporation of Missouri Filed May 10, 1962, Ser. No. 193,724 20 Claims. (Cl. 72-294) This invention relates` to bending apparatus, and more particularly to apparatus for bending the margins of sheet metal shingle blanks to form hooksat the four edges `of the blanks. t i p The invention is particularly concerned with an apparatus for forming shingles of the type shown in my United States Patent 2,830,546 issued` April 15, 1958 having a top hook on the outside, a butt hook Ion the inside, a right end hook on the outside and aV left end hook on the inside, from individual iiat sheet metal single blanks such as shown in FIG. l of said patent, among the several objects of the invention being noted the provision of apparatus for this purpose which is adapted to be mounted in a truck or trailer and moved `to various lield locations forforming hooks on iiat shingle blanks directly on the job; the provision of.` such happaratus which is adapted to operate upon blanks of diiierent sizesythe provision of such apparatus enablingV easy and rapid` manual placement of blanksrstin position for bending two of the hooks (more particularly the top and right end hooks), then in position for bending the other two hooks' (the butt and left end hooks), and easy and rapid manual removal ofthe completed shingles; the provision of such apparatus adapted to be powered by compressedair such as is readily obtainable in the lield as by providing a compressor on the truck or trailer, powering. the compressor from the engine of the truck or electrically where electrical power is readily available; the provision of such apparatus adaptedfor forming thin or thick butt hooks,'

and for forming tapered buttphooks; and "the provision of apparatus such as describedf which is:` relatively economical to construct and operate, `thereby enabling economical production in the field of completed shingles from flat blanks. Other objectsv and features will berlin' part" apparent and in part pointed out hereinafter.

Theinvention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims. m

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIG. 1 is a plan of an apparatus constructed in accordance with this invention, showing in phantom the range lof sizes of blanks which may be handled by the ap paratus; p

FIG. 2 is a front elevation of :the apparatus;

FIG. 3 is a right `end elevation of the apparatus, on a larger scale than FIGS. 1 and 2, and With a right end frame member broken away to show parts on the inside of said member; m j

FIG. 4 is "an enlarged vertical section taken on line 4 4 of FIG. l; m

FIG. 5 is an enlarged vertical section taken online 5 5 of FIG. l; f- FIG. 6 is an enlarged vertical section taken on line 6 6 of FIG. 1;

FIG. 7 is an enlarged vertical sectiontaken on line 7 7 65 of FIG. l; l .i C

FIG. 8 is a fragment of FIG. 4 showing theubending ofatophook;Y i A, m.

FIG. 8A is an enlargedM section showing how certain indentation are formedin thetop hook; FIG. 9 is a fragment of FIG. 5 showing the a right end hook; -A u m p 3 bending of 3,191,419 Patented June 29, 1965 ice FIG. l() is a fragment of FIG. 4 showing the bend-1 ing of a thin butt hook;

FIG. 1l is a fragment of FIG. 6 showing the bending of a left end hook; j 1

FIG. 12 is a fragmentof FIG. 4 showing how proi vision is made for bending a thick butt hook; and

FIG. 13is a diagram of the pneumatic system of the apparatus.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings,

Referring first to FIG. l of the drawings,` reference character Bl designates a` sheet metal blank (a sheet aluminum blank, for example) the margins of which are to be bent to form the blank into a shingle with a top` hook 21 (see FIGS. l and 8A) on What may be termed the outside of the shingle, a butt hook 29 (see FIG. l0) on the inside, a right end hook 43 (see FIGS. l andr9) on the outside and a left end hook 49 (see FIG. 1l) on the inside. Blank B1 is initially flat and corresponds essentially to the blank shown in FIG. `l of my U.S. Patent 2,830,546. The top hook 21 is to be an angled hook having indentations such as indicated at, 15 in said U.S.V

patent` and in FIG. 8A hereof. The butt hook is to be generally 3of U-shape, anda thin (narrow)jU-shape` or a thick (wide) U-shape may be desired. Generally speaking, a thin butt hook is desiredfor shingles used for roofthickness from `one end thereof to the other) for pur-- poses such as indicated in my U.S. Patent 2,975,818 issued March'Zl, 1961.

The blank Blrindicated in FIG. '1 represents a smaller size of blank that may be handled by the apparatus. At

B2 is indicated a larger blank, representing the largest size of blank that may be handled.

The apparatus of this inventionis adapted to bend `the margins of a blank such as B1 or B2 to form thestated hooks, also to form the indentations 15 in the top hook 21, so that the indentations need not be yinitially formed in the blanks. In general, the apparatus comprises agenerally rectangular table 2, which is somewhat larger than the largest blank B2 to be handled. A blank is placed on thetable with its rear margin projecting rearward from the rear edge of the table and its right end margin projecting from the right edge of the table, and means is provided for substantially simultaneously effecting bending up and over of the projecting rear and right end margins of the blank to form the top hook 21 and right end hook 43. Theindentations 1S are formed in the course of this operation.` The blank, with the top and right end hooks so formed, is then repositioned on the table withits frontnmargin projecting forward from the front edge' of the table and its left end margin projecting fromv the left edge of the table, and means is provided for then` effecting bending down and under of the projecting front and left end margins of the blank to form the butt hook 29 andthe left end hook 49.

Table 2 comprises a generally rectangular plate with cutouts 2a and 2b at its left rear and right front corners', respectively; It is secured on a` supporting frame generally designated 4. This frame 4 includes a lateralfront bar 6, inside and outside lateral bars 8 and 10 at the rear, a left end bar 12, and inside and outside right end bars 14 and 16. Front bar 6 projects to the left beyond left end bar 12. The inside rear bar has its ends supported on andjsecured` to left and rightV frame bottom plates 18 and 20. The frame 4 stands on left and right front legs 22V and 24 and left and right rear legs 26 and 28. v

The table is secured on the frame with its rear edge 30 generally flush with the rear face of thek inside rear bar 8 (see FIG. 4) and with its right end edge 32 somewhat outward of the outside face of the inside right end bar 14-(seeFIG. 5). A bending blade 34 (see particularly FIG. 6) constituting an extension of the table is secured in a groove in the top of the table at its left end, and projects out to the left beyond the left end bar 12. The louter edge of this blade 34 constitutes the left end edge of the table. As will appear, the left end margin of a blank is bent down and around and under this blade to form the left end hook 49 on the blank. The table 2 projects forward to some extent from the front bar'6. Secured tothe latter underneath the projecting portion of the table is an anvil bar 36 which extends the full length of the front of the table and which constitutes an extension of the table. This bar '316 has a groove 38 receiving the projecting portion rof the table and a forwardly extending ange 40 along the top thereof. Se-

cured on top of this ilange is a hard steel insert 42.v

Flange 40 may taper in thickness from its left end to its right end. Its taper may be such, for example, that the combined thickness ofthe ange and insert 42 at their left end may be three-eighths inch, and at their right end one-quarter inch. The front edge of flange 40 constitutes the front edge of the table, and the butt hook 29 is formed on a blank around this edge, as will appear. The anvil b ar is removably secured toY bar 6 asbyV screws 44.

In order to enable the operator accurately to position a blank for first bending its rear and right margins to forni the top and right end hooks, gauge means is providedpon table 2 engageable by the edges of a blank for i locating it in proper position toward the rear and the right. of the table.

As shown in FIG. l for blank B1, this comprises three studs 46, 48 and 50 each threaded in a tapped hole in the table and extending up from the table. The tapped holes, each of ywhich is designated 5,2, areso located, in relation to the size of blank B1, that .with the left edge of blankl B1 engaging stud 46 and the buttedge of the blank engaging studs A48 and 50; lthe proper overhang of the rear and right margins of the blank is obtained. Similarly, means is provided on table 2 engageable bythe top and right edges of blank B1 after formation of the top and right end hooks on the blank for locating theblank in proper position toward the front and left of the table for bendingV the butt and left end hooks. Asshown, this-comprises studs 54 and 56, in

Vaddition to stud 48, `also removably threaded in tappedV holes '52 in the table, so located that with the top edge'of the blank B1 engaging studs 54 and 48 and the right edge of the blankengaging stud 56 (after formation ofthe top and right end hooks), the proper` overhang of the front and left margins of the blank is obtained; Additional holes such as indicated at 52a may be provided in the table for repositioning the blank-locating studs for operation on blank B2, and further holes (not shown) may be provided for repositioning the studs for handling other sizes of blanks. f

The means for effecting the bending up and over of the overhanging rear and right end margins of a blank to form the top hook 21 and right end hook 43 is shown to comprise a combination blank clamp and bending blade assembly generally designated 58, and pivotally mounted rear and right bending bars 60 and 62. Assembly 58 comprises a vertically movable rear clamping bar 64 which extends overrthe table 2 from one end thereof to the other and which is adapted to be moved up and down by a pair of vertical air cylinders each designated 66. Each of these air cylinders is a double-acting air cyhnder having a port 68 at its upper end and a port '70 at its lower end, a piston 72, and a piston rod 74 extending from the piston through the lower end of the cylinder to akconnection at '76 with a foot 78 ona respective rear leg 26, 28. A rod 80 is connected at 82 to the upper end of each cylinder and extends upward through a hole in the respective bottom frame plate 18, 20 and a guide 84 on the latter to a connection at 86 vwith a respective end of the clamp bar. The arrangement is such that by supplying air under pressure to cylinders 66 through their upper ports 68'and ventingtheir lower ports 70, the cylinders are raised to raise clamp bar 64, and by supplying air underpressure to cylinders 66 via their lower ports 70 and venting their upper ports, the cylinders and clamp bar 64 are lowered.

Rigidly secured to clamp bar 64 and extending forward therefrom over the right end of the table 2 is a right-hand clampingbar 88. This'moves up and down With-clamp bar 64. 'Ihe latter is spaced somewhat forward of the rear edge of table 2, and clamp bar 8 8 is spaced somewhat to the left of the right edge of the table. Clamp bar 64 has a bending blade 90 secured to and extending rearward from its bottom. Similarly, clamp b ar 88 has a bending blade 92 secured to and extending to the right from its bottom. -When assembly 58 is moved down, bars 64 and 88 (which together constitute any L-shaped clamp assembly) clamp a blank B1 (properly positioned on the table by utilizingrstuds 46, 48 and 50) down on table 2 adjacent the rear and right margins of the blank, with these marginsextending out from under the bending blades 90 and 92. Then, the rear and right bending bars 60 and 62 are swung around, as will be made clear, to bend the rear margin of the blank up and around over the blade 90 and to bend the right end margin of the blank up and around over the blade 92. The rearwardly projecting portion of blade 90 is of tapered cross section to j provide the desired angling of the top hook of the shingle,

and is provided with slots 94 for accommodating downward depression of the rear margin of the blank as it is bent around the blade by projections 96 on the rear bending bar 60 to form the indentations 15.

The rear bending bar 60 extends from end-to-end of the table 2 at the rear thereof, being of rectangular cross section with trunnions 98 at its ends journalled in bearing blocks 100 mounted on the bottom frame plates 18 and 20, bar 60 thereby being pivoted for swinging movement on a horizontal axis parallel to theV rear edge of the table and bending blade 90. Each trunnion has a pinion 102-secured thereon. vHorizontal racks 104 operable by horizontal air cylinders 106 mesh with the pinions.

Each air cylinder 106 is a double-acting cylinder, the cylinder at the left being mounted on the left frame bottom plate 18 and the cylinderl at the right being mounted on the right frame bottom plate 20. A piston rod 108 extends rearward from a piston 110 in each cylinder to a connection with the respective rack. Each of cylinders 106 has a port 112 at its forward end `and a port 114 at its rearward end. With the pistons 110, piston rods 108 and racks 104 retracted (FIGS. 1, 3 and 4), rear bending bar 60 occupies the retracted position best shown in FIG. 4, in which it is vertically positioned at the rear of the inside rear frame bar 8 with its upper edge just below the top of table 2, overhung by the rear margin of the blank. On admitting airl under pressure through forward ports 112 and venting rearward ports 114 of cylinders 106, racks 104 are driven rearward to swing bar y 60 counterclockwise up and aroundvto bend the rear margin of the blank up and around the rear edge of the bending blade to form the top hook (see FlG. 8).

By admitting air under pressure through rearward ports i 114 and venting forward ports 112, the racks are retracted to return bar 60 to retracted position.'

The right end bending bar 62 extends along the right end of the table 2, having a trunnion 116 at its forward end journalled in bearing blocks 118 on the right frame bottom plate 20, bar 62 being thereby pivoted for swinging movement Von a horizontal axis parallel to the right edge of the table and bending blade 92. Trunnion 116 has a pinion 120 secured thereon. A rack 122 operable by an air cylinder 124 (see FIG.7) meshes with the pin-` ion 120. Cylinder 124 is a double-acting air cylinder, mounted underneath table 2 toward the right end thereof. A piston rod 126 extends from a piston 128 in cylinder 124 to a connection with the rack 122. Cylinder 124 has a port 130 at its left end and a port 132 at its right end. With piston 128, piston rod 126 and rack 122 retracted (FIGS. 1 and 7), the right end bending bar 62 occupies the retracted position best shown in FIG. 5 in which it is vertically positioned on the outside of the inside right end frame bar 14 with its upper edge-just below the top of table 2, overhung by the right margin of the blank. On admitting air under pressure to the leftend of cylinder 124 Via port 130 and venting port 132, rack 122 is driven to the right to swing bar 62 counterclockwise as viewed in FIG. 5 up and around to bend the right margin of the blank up and around the edge of blade 92 to form the right end hook (see FIG. 9). By admitting air under pressure through port 132 and venting port 130, rack 122 is retracted to return bar 62 to retracted position.

The means for effecting bending down and under of the overhanging front and left end margins of a blank to form the butt hook 29 and the left end hook 49 is shown to comprise a blank clamping and bending assembly generally designated 134, andpivotally mounted front and left bending bars 136 and 138. Assembly 134 comprises a vertically movable iront clamping and bending bar 140 which extends over the table 2 from one end thereof to the other and which is adapted to be moved up and down by a pair of vertical air cylinders each designated 142. Each of these air cylinders is a doubleactingair cylinder having a port 144 at its upper end and a port 146 at `its lower end, a piston 148, and a piston rod 150 extending from the piston through the upper end of the cylinder to a connection at 152 with a respective end of the bar 140. Each cylinder 142 is mounted on a respective front leg 22,24. The arrangement is such that by supplying air under pressure to cylinders 142 through their lower ports 146 and venting their upper ports 144,

bar 140 is raised as in FIGS. 2-4, and .by supplying air under pressure to cylinders 142 via their upper ports `144 and venting their lower ports 146, bar 140 is lowered as in FIG. 10.

Bar 140 has a recess 154 extending lengthwise at the bottom rear thereof. The forward side of this recess is located slightly outward from the front edgeof flange 40 of anvil bar 36. This provides a downwardly extending bending bar portion 156 at the bottom front of the bar 140 adapted, on downward movement ofthe bar, to bend the overhanging front margin of a blank downward around the front edge of iiange 49, the front margin of the blank then extending vertically downward. A presser plate 158 backed by compression springs 160 is vertically slidable in recess 154 and is adapted, on downward movement of bar 149, to engage and clamp the blank, after which bar 140 continues its downward movement as permitted by compression of springs 160 to eiect the downward bending of the front margin of the blank. Plate 158 is mounted on the lower ends of bolts 162 vertically slidable in holes in bar 140, and springs 16() sur` round the bolts.

`Rigidly secured to bar 140 and extending rearward therefrom overv the left end bending blade 34 on table 2 is a left-hand clamping bar 164. This moves up and down with bar 140 and is adapted, on downward movement of bar 140, to clamp a blank adjacent the left mary gin of the blank. Bars 140 and 164 together constitute Bar` 136 has pivots 168 journalled in bearing blocks 170, thereby being pivoted for swinging movement on a horizontal axisV parallel to the front edge of the table (i.e., the front edge of ilange 49). It is adapted to be swung clockwise from its FIG. 4 retracted position to its FIG. 10 advanced position and back to retracted position by an air cylinder 172. This is a double-acting air cylinder pivoted at one end (its rear end) as indicated at 174 on a bracket 176 secured to bar 8 and having a piston rod 178 extending through its forward end from a piston 180 therein. The piston rod 178 has a clevis 182 at its end pin-connected as indicated at 184 to an arm 186 on bending bar 136. Cylinder 172 has a port 188 at its rear end and a port 190 at its forward end. The arrangement is such that by supplying air under pressure to cylinder 172 through its forward port 190 and venting its rearward port, rod 178 is retracted` to retract bending bar 136. By supplying airk under pressure to cylinder 172 through its rearward port 188 and venting its forward port 190, rod 178 is advanced to swing bar 136 clockwise for bending a butt hook.

The left end bending bar 138 extends along the left end ofthe table 2, having a trunnion 192 at its rearward end journalled in bearing blocks 194 mounted on the outside of the left end frame bar 12, and thereby being pivoted for swinging movement on a horizontal axis parallel to the left end edge of the table (i.e., the outer edge of blade 34). Trunnion 192 has a pinion 196 secured thereon. A vertically extending rack 19S operable by a vertical air cylinder 280 meshes with the pinion 196. Cylinder 2081s a double-acting air cylinder mounted on a leg 262 extending down from bearing blocks 194. A piston rod 204 extends upward from a piston 206 in cylinder 280 to a connection with the lower end of rack 198. Cylinder 20) has a port 208 at its upper end and .a port 210 at its lower end. With the piston 206,., piston rod 204 and rack198 raised, the left end bending bar 138 occupies the retracted position best shown in FIG. 6 in -which it is vertically positioned outward of blade 34 with its lower edge just above the level of the top of blade 34, in position to overlie the left'margin of a blank. On admitting air under pressure to the upper end of cylinder 261i) via port 268 and venting its lower end via port 210,

rack 198 is pulled down to swing bar 138 counterclockwise as viewed in FIG. 6 to bend the left end margin` of the blank around blade 34 to form the left end hook (sce FTG, l1). By admitting air under pressure through port 210 and venting port 208, rack 198 is. raised to retract bar 138.

As above mentioned, ilange 40 is tapered'to provide" the desired tapered conformation of the butt hook 29. Bending blade and bending bar 60 are so formed at their right ends as to provide the desired outward offset of the right end of the top hook 21. for example, by providing a half-round boss 212 on the blade 90 adjacent its right end and a corresponding recess 214 in bar 68. It will be observed from my aforesaid U.S. patents that the shingles have what amounts to a nailing tab at the top `right corner with a nail-receiving hole therein. This hole is preformed in the blanks used in apparatus of this invention. The nailing tab is formed as an extension of the top hook, and is later attened down when the shingle is nailed in place.

Four manually operable spring-return four-way valves V1, V2, V3 and V4 are provided for manually controlling the operation of the apparatus. Each of these values has a stem 216 with a push button 21S thereon, andall four valves are located under table 2 with their push buttons 218 accessible via holes in the table. Valves V1 and V2 are paired adjacent the left rear corner of the table, and` valves V3 and V4 are paired adjacent the right front corner of the table. Valves V1-V4 are identical, each ha ing an inlet represented at 220 which is connected to a` source of compressed air (not shown), a vent `repre- This is accomplished,

7 sented at 222 and two transfer ports represented at 224 and 226 (see FIG. 13).

Port 224 of valve V1 is connected as indicated at 223 to the upper ports 63 of cylinders 66, and port 226 of valve V1 is connected as indicated at 231) to the lower ports 70 of cylinders 66. When valve V1 is off, compressed air is supplied from the valve inlet via 228 to the upper ends of cylinders 66, and the lower ends of these cylinders are vented via 230 and the vent 222 of valve V1. This holds the rear clamp bar 64 and the rightehand clamp bar 88 raised. When the button of valve V1 is pushed down, compressed air is supplied from the valve inlet to the lower ends of cylinders 66 via 230 and vented from their upper ends via 228, and this lowers clamp bars 64 and SS.

Port 224 of valve V2 is connected as indicated at 232 to the lower ports 146 of cylinders 142, and port 226 of valve V2 is connected as indicated at 234 to the upper ports 144 of cylinders 142. When valve `V2 is off, compressed air is supplied from the valve inlet via 232 to the lower ends of cylinders 142 and air is vented from their upper ends via 234 and the valvevent. This holds the front clamping and bending bar 140 and the left-hand clamping bar 164 in raised position. Whenthe button of valve V2 is pushed down, compressed air is supplied from the valve inlet to the upper ends ofthe cylinders 142 via 234 and vented from their lower ends via 232, and thi-s lowers bars 140 and 164.

Port 224 of valve V3 is connected as indicated at 236 l to the rear end ports 114 of cylinders 106and the right end port 132 of cylinder 124, and port 226 of valve V3 is connected as indicated at 238 to the forward end ports 112 of cylinders 106 and the left end port 130 of cylinder 124. When valve V3 is off, compressed air is supplied from its inlet via 236 tothe rearward ends of cylinders 1116 and air is vented from their forward ends Via 238 and the valve vent.V This holdsthe rear bending bar 60 in retracted position. Compressed air is also supplied to the right end of cylinder 124 and vented from its left end to hold the right end bending bar 62A in retracted position. When the button of valve V3 is pushed down, compressed air is supplied from the valve inlet via 238 to the forward ends of cylinders 106 and the left end of cylinder 124 and air is vented from the rear ends of cylinders'106 and the right end of cylinder 124 to actuate the rear bending bar 66 and the rightend bending-bar 62.

Port 224 of valve V4 is connected as indicated at 246 to the forward end port 190 of cylinder 172 and the lower end port 210 of cylinder 2110, and port 226 of valve V4 is connected as indicated at 242 to the rearward end port 183 of cylinder 172 and the upper end port 203 of cylinder 200. When valve V4 is oif, compressed air is supplied from the valve inlet via 240 to the forward end of cylinder 172 and air is vented from the rearward end of cylinder 172 via 242 and the valve vent. This holds the front bending bar 136 in retracted position. Compressed airis also supplied via 240 to the lower end of cylinder 206 and air is vented from its upper end via 242. This holds the left end bending bar 138 in retracted position. When the button of valve V4 is pushed down, compressed air is supplied from the valve inlet via 242 to the rearward end of cylinder 172 and the upper end of cylinder 200 and air is vented from the forward end of cylinder 172 and the lower end of cylinder 200 via 241B to actuate the front bending bar 136 and the left end bending bar 138.

Operation of the above-described apparatus lows:

Assuming that a run of blanks B1 are to have their marginsbent, the blank-positioning studs 46, 48, 50, 54 and 56 are located as shown in FIG. 1. With all four valves V1-V4 off, and consequently with assembly S8 (comprising rear and right clamp bars 64 and 88) in raised retracted position, assembly 134 (comprising front and left clamp bars 140 and 164) in raised retracted position, and al1 lfour bending bars 60, 62, y1.36 and 138 in reis as foltracted'position, a blank B1 is positionedontable 2 with its left end engaging stud 46 and its butt edge engaging studs 43 and 50. These studs constitute gauge means for accurately locating the blank in its first working position toward the rear and right with proper overhang of its rear'and right margins beyond the rear edge 3i? and right edge 32 of table 2.

With the blank B1 thus properly located in its rst working position, the operator presses the button of valve V1 to lowerl the rear and right clamp bars 64 and 88 (see FIGS. 8 and 9 showing thesevbars so lowered). Blade 96 on bar 64 comes down into engagement with the blank to clamp itdown on the table adjacent the rear margin of the blank and bladev92 on bar 88 comes down into engagement with the blank to clamp it down on the table adjacent the right margin of the blank. Holding down the button of valve V1 to maintain the blank clamped, the operator presses the button of valve V3 to actuate the rear bending bar 60 and the right end bending bar 62. Bar 61) swings counterclockwise from its FIG. 4 to its FIG. 8 and 8A position to bend the overhanging rear margin of the blank around the rear edge of blade 99 and down on top of'this blade to form the top hook 21 on the blank. Projections 96 on bar 619 form the identations 15 in the top hook k.as-'shown in FIG. 8A. Bar 62 swings counterclockwise from its FIG. 5 to its FIG. 9 position to bend the overhanging right end margin of the blank around the right edge of blade 92 and down on top of this blade to form the right end hook 43 on the blank.

The button of valve V3. is then released for retraction of i bending bars 61B and 62, after which valve V1 is released for retraction (raising) of clamp bars 64 and 88. This frees the blank B1 so that the operator mayreadily shift the blank to its second working position toward `the front and left, which is accurately determined by engagement of the top or rear edge of the now half-formed blank with studs 54 and 43 and the right edge of the blank with stud S6. VThese studs constitute gauge means for accurately locating the blank in its said second working position toward the front and left with proper overhang of its front and left margins beyond the front edge of ange 4i) of anvil bar 36 and the left edge of blade 34.

With the blank thus properly located in its second working position, the operator lpresses the button of valve VZ to lower the front and left clamp bars 141i and 164 (see FIGS. l0 and ll showing these bars so lowered). As bar 146 moves downward, the spring-backed presser plate 158 comes into clamping engagement with the blank to clamp it down adjacent the front margin of the blank. After initial engagement of the presser plate with the blank, bar 146 continues its downward movement and bending bar portion 156 of bar 141i bends the overhanging front margin of the blank vertically downward around the front edge of ilange 46. Bar 164 comes down into engagement with the blank to clamp it down on blade 34 adjacent the left margin of the blank. Holding down the button of valve V2 -to maintain the blank clamped, the operator presses the button of valve V4. to actuate the front bending bar 136 and the left end bending bar 138. Bar 136 swings clockwise from its FIG. 4 to its FIG l0 position to bend the now downturned front margin of the blank in underneath the flange 46 to form the butt hook 29 on the blank. Bar 133 swings counterclockwise from its FIG. 6 to its FIG. ll position to bend the overhanging left margin of the blank around the left edge of blade 34 and underneath this blade to form the left end hook 49 on'the blank.l

The button of valve V4 is then released for retraction `of bending bars 136 and 138, after which valve V2 is released for retraction (raising) of clamp bars and 164. This frees the fully formed blank for removal by sliding it toward the left and forward to unhook the left end hook 49 from blade 34 and to unhook the butt hook 29 from the flange 4?.

Bending of a larger blank, such as a blank B2 illustrated in FIG. 1, is carried out in the same manner as above described, except, of course, that the positiongauge studs are relocated for locating the blank to have the proper overhang in the first and second positions.

As above described, with filler strips 165 and 166 on the front bending bar 136, a thin butt hook is formed around flange 4G. If desired to form a thick butt hook, filler strips 165 and 166 are removed from bar 136 and fastened to anvil bar 36 underneath flange 4t), suitable screw holes being provided in the anvil bar for this purpose. FIG. 12 also shows the addition to the front bending bar 136 of means for punching a weep hole in the base of the butt hook, such holes being desirable in the butt hooks offshingles used for siding. As shown, this means comprises a bracket 248 on bar 136 carrying a punch 25i) adapted to pierce a weep hole in the base of the butt hook as bar 136`is swung clockwise to form the butt hook. Filler strip"165 is shown as recessed at 252 (see FIGS. 2, 4 and 10)` to accommodate `the punch. A plurality of such `piercing devices may be provided on bar 136 to punch a plurality of weep holes in the base of the butt. It will be apparent that butt hooks of intermediate thicknessmay be bent by securing strip 165 under flange 40, leaving strip 166 on front bending bar 136.

In view of the above7 it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is: t i

1. Apparatus for bending the margins of a generally rectangular sheet metal blank to form first, second, third and fourth hooks at the four edges thereof, the first and second hooks extending along first and second margins of the blank at right angles to one another on one face of the blank and'the third and fourth hooks extending along the other two margins of .the blank at right angles to one another on the other face of the blank, said apparatus comprising a table structure having first and second edges at" right angles to one Vanother and third and fourth edges at rightangles to one another,' said table structure being adapted to receive a blank in a first position wherein its first and second margins extend beyond the first and second edges of said table structure, means at said first and second edges of said table structure for bending said first and second margins of the blank in sai-d first position in one direction to form the first and second hooks, the blank being shiftable relative to the table structure after formation of the first and second hooks to a second position wherein the third and fourth margins of the blank extend beyond said third and fourth edges of the table structure, and means at said third and fourth edges of said table structure for bending said third and fourthmargins of the blank in said second position in the opposite direction to form the third and fourth hooks, the means for bending the first and second margins of the blank comprising rst and second vertically movable clamping bars each carrying a bending blade adapted to clamp the blank to the table structure, and first and second bending bars mounted for movement to bend the first and second margins of the blank up and around the edges of said bending blades and over the latter, the means for bending the third margin of the blank comprising a third verticallymovable bar carrying yielding presser means for clamping the blank to the table structure and'means for bending down the third margin of the blank around said third edge 'of the table, and a third bending `bar adapted to move in under said third edge of the table and bend in the third margin able clamping bar adapted to clamp the blank to the table structure and a fourth bending bar mounted for movement to bend the fourth margin of the blank downward around the fourth edge of :the table structure and under the latter.

2. Apparatus as set forth in claim 1 wherein the fourth bending bar is pivoted for swinging movement on an axis parallel to the fourth edge of the table.

3. Apparatus as set forth in claim 1 wherein the first and second clamping bars are secured together as a unit, and the third and fourth clamping bars are secured together as a unit.

4. Apparatus as set forth in claim 3 including fiuid pressure means and a control therefor for moving the first and second clamping bars up and down, fluid pressure means and a control therefor for actuating the first and second bending bars, fluid pressure means and a control therefor for actuating the third and fourth clamping bars, and iuid pressure means and a control therefor for actuating the third and -fourth bending bars.

5. Apparatus for bending the margins of generally rectangular sheet metal shingle blanks of various sizes to form an outside top hook at one long edge of the blank, an outside end hook at one end of the blank, an inside butt hook at the other long edge of the blank, and an inside end hook at the other end of the blank, comprising a generally rectangular table larger than the largest size of blank to be handled, said table having front and rear edges longer than the length of the largest blank to be l handled and end edges longer than the width of the largest blank to be handled, said table being adapted to receive a` blank in a first position wherein the rst and second margins of the blank from which the top and outside end hooks are to be formed extend beyond the rear and one end edge of the table, means at said rear and one end edge of said table for bending up `and over said first and second margins of the blank in said first position to form them into said top-hook and said outside end hook, the blank then being shiftable on the table to a second position wherein the third and fourth margins of the blank from which the butt hook and the inside end Vhook are to be formed extend beyond the front and the other end edge of the table, and means at said front and other end edge of said table for bending said third and fourth margins of the blank in said second position down and around said front and other end edge of the table to yform them into said butt hook and said inside end hook, the means for bending the first and second margins of the blank to form the top hook and outside end hook comprising a first vertically movable clamping bar extending over the table adjacent its rear and a second vertically movable clamping bar extending over the table adjacent one end edge of the table, said first clamping bar having a rearwardly extending bending blade at the Ibot- 'tom and said second bar having an outwardly extending bending blade at the bottom, a first bending bar extending along the rear edge of the table mounted for movement to bend the rear margin of the blank up and over 4the blade on said first clamping bar, and a second bending bar extending along said one end edge of the table mounted for movement to bend the second margin of the blank up and over the blade on said second clamping bar,

the means for bending the third and fourth margins of the blank to form the butt hook and inside end hook `comprising a third vertically movable clamping bar extending4 over the table adjacent its front edge, said third clamping bar carrying yielding pressure means for clamping the blank to the table and having a downward extension in front of said presser means for bending the front margin of the blank down around `the front edge of the table, a third bending bar extending along the front edge of the table adapted to move in under the front edge of the table, a fourth vertically movable clamping bar extending over the table adjacent the other end edge of the table, and a fourth bending bar extending along said other end edge of the table mounted for movement to bend the fourth margin of the blank down around and under said other end edge of the table'.

' 6. Apparatus as set forth in claim S wherein said third bending bar is mounted for swinging movement on a horizontal axis parallel to the front edge of the table, and is adapted to swing in under the front edge of the table, and said fourth Y bending bary is pivoted for swinging movement on a horizontal axis parallel to said otherrend` edge of the table.

7. Apparatus as set forth in claim wherein said first and second clamping bars are secured together in a first L-shaped assembly, and said third and fourth clamping bars are secured together in a second L-shaped assembly.

S. Apparatus as set forth in claim '7 including fluid pressure means an-d a control therefor for raising and lowering said first L-shaped assembly, uid pressure means and a control thereforV for swinging said first and second bending bars, iiuid pressure means and a control therefor for raising and lowering said second L-shapedV assembly, and fiuid pressure means and a control therefor `for swinging said third and fourth bending bars. s

9. Apparatus as set forth in claim 8 wherein each of said controls includes a push button accommodated in a hole in the table, the push buttons being located so as to be accessible from the top ofthe table with, a blank either in the first or second position on the table.

10. Apparatus as set forth in claim '9 wherein the push buttons for the first-mentioned and third-mentioned controls are located adjacent one another toward the rear and bending bar carries means for piercing a hoie in the Vbutt hook.

fication of the thickness of the front edge of the table and modification of the third bending lbar for bending 'butt hooks of different thickness. v

1d. Apparatus as set forth in claim 13 comprising filler strip means adapted alternately for attachment under the front edge of the table or on the upper edge of the third bending bar for bending butt hooks of different thickness.

i5. ln an apparatusfor bending a margin of a sheet metal blank to form a hook, means having an edge around which a margin of a blank is adapted to be bent to form a hook, means for partially bending said margin around said edge, a bending bar adapted to move in and further bend the partially bent margin around said edge to complete the formation of the hook, and filler strip means adapted alternatively for attachment to said means at sai-d edge or to said bending bar for ibending hooks of different thickness.

16. ln an apparatus as set forth in claim 15, said bending bar being mounted for swinging movement on an axis parallel to said edge.

y f7. Apparatus for bending the margins of a generally rectangular sheet metal blank to form first, second, third and fourth hooks at the four edges thereof, the first and second hooks extending along first and second margins of the blank at right angles to one another on one face of the blank and the third and fourth hooks extending along the other two margins Vof the blank yat right angles to one another on the other face of the blank, saidv apparatus comprising a table having first and second edges at right angles to one another and third and fourth edges at right angles to one another, said table being adapted to have a blank positioned thereon with the iirst and second margins of the blank extending beyond the first and second edges of the table for forming the first and second 13. Apparatus as set forth in claim 5 adapted for modii2 hooks and subsequently positioned thereon with the third and fourth margins of the blank extending beyond the third and fourth edges of the table for forming the third and fourth hooks after the formation of the first and second hooks, means for bending the first and second margins of theV blank .as first positioned on the table in one direction to form the first and second hooks, and means for subsequently bending the third and fourth margins of the blank as subsequently positioned on the table to form the third and fourth hooks, one of said bending means comprisingl two bending blades arranged at right angles to one another and movable downward from a raised retracted position above the table to a lowered position for clamping the blank along the respective edges of the table with the respective margins of the blank projecting out from under said blades, and two bending bars mounted for movement to bend the respective margins of the blank up and around the edges of the blades and over the latter, said blades, on moving back upward to retracted position, lifting the blank by the hooks formed as a result of operation of said bending bars and thereby permitting the blank to be disengaged from said blades, the other of said bending means comprising clamping means operable independently of said blades for clamping the blank along the respective edges of the table while said blades are raised, and bending bars mounted for movement to bend the respective edges of the blank under the respective edges of the table and operable independently of the first-mentioned bending bars.

f8. Apparatus for bending the margins of a generally rectangular sheet metalblank to forni first, second, third and fourth hooks at the four edges thereof, the first and second hooks extending along rst and second margins of the blank at right angles to oneanother 0n one face of the blank and the third andY fourth hooks extending along the other two margins Vof the blank at right angles to one another of the other face of the blank, said apparatus comprising a table having rst and second edges at right angles to oneanother and third and fourth edges at right angles to oner` another, sai/d table being adapted to have a blank positioned thereon with the first and second margins ,of the blank extending beyond the first and second edges of the table, means for bending up and over the first and second margins of the blank so positioned on the table `to form the first and second hooks comprising first and second vertically movable bending blades arranged at right angles to oneganotherl and movable downward from a raised retracted position above the table extending alongthe first and second edges of the table to a lowered position for clamping the blank to the table along said rst and second edges of the table with the first and second margins of the blank projecting out from under said blades, and first and second bending bars mounted for movement to bend the first and second margins of the blank up and around the edges of said bending blades and over the latter, said blades, on moving back upward to retracted position, lifting the blank away from the table by the first and second hooks, thereby permitting the blank with the first and second hooks formed thereon to be disengaged from said blades and then replaced on the table with the third and fourth margins of the blank extending beyond said third and fourth edges of the table, means for then bending said third and fourth margins of the replaced blank downward and around said third and fourth edges of the table to form the third and fourth-hooks comprising clamping means movable downward from a raised retracted position above the Ytable to a lowered position for clamping the blank to thetable along its said third and fourth edges, and third and fourth bending bars mounted for movement inward under the third and fourth edges of the table to form the third and fourth hooks around said third and fourth edges of the table, said clamping means and said third and fourth lbending bars being operable independently of said blades and said rst and second bending bars, and means for operating said blades and rst and second bending bars and then subsequently operating said clamping means and third and fourth bending bars.

19. Apparatus as set forth in claim 18 wherein said table is generally rectangular and larger than the largest size of blank to be handled, said first and second edges of the table being constituted by one long edge and one end edge of the table, and said third and fourth edges of the table being constituted by the other long edge of the table and the other end edge of the table, and wherein gauge means is provided on the table for positioning the blank irst for forming the rst and second hooks and for subsequently positioning the blank for forming the third and fourth hooks.

20. Apparatus as set forth in claim 18 wherein said References Cited bythe Examiner UNITED STATES PATENTS 329,149 l0/85 Eager et al. 153--17 655,903 8/00 Martin 153-17 655,904 8/00 Martin 153-17 2,975,818 3/61 Rippe 153--12 3,009,179 11/61 Schramm 153-12 CHARLES W. LANHAM, Primary Examiner.

WILLIAM I. STEPHENSON, Examiner. 

1. APPARATUS FOR BENDING THE MARGINS OF A GENERALLY RECTANGULAR SHEET METAL BLANK TO FORM FIRST, SECOND, THIRD AND FOURTH HOOKS AT THE FOUR EDGES THEREOF, THE FIRST AND SECOND HOOKS EXTENDING ALONG FIRST AND SECOND MARGINS OF THE BLANK AT RIGHT ANGLES TO ONE ANOTHER ON ONE FACE OF THE BLANK AND THE THIRD AND FOURTH HOOKS EXTENDING ALONG THE OTHER TWO MARGINS OF THE BLANK AT RIGHT ANGLES TO ONE ANOTHER ON THE OTHER FACE OF THE BLANK, SAID APPARATUS COMPRISING A TABLE STRUCTURE HAVING FIRST AND SECOND EDGES AT RIGHT ANGLES TO ONE ANOTHER AND THIRD AND FOURTH EDGES AT RIGHT ANGLES TO ONE ANOTHER, SAID TABLE STRUCTURE BEING ADAPTED TO RECEIVE A BLANK IN A FIRST POSITION WHEREIN ITS FIRST AND SECOND MARGINS EXTEND BEYOND THE FIRST AND SECOND EDGES OF SAID TABLE STRUCTURE, MEANS AT AND FIRST AND SECOND EDGES OF SAID TABLE STRUCTURE FOR BENDING SAID FIRST AND SECOND MARGINS OF THE BLANK IN SAID FIRST POSITION IN ONE DIRECTION TO FORM THE FIRST AND SECOND HOOKS, THE BLANK BEING SHIFTABLE RELATIVE TO TE TABLE STRUCTURE AFTER FORMATION OF THE FIRST AND SECOND HOOKS TO A SECOND POSITION WHEREIN THE THIRD AND FOURTH MARGINS OF THE BLANK EXTEND BEYOND SAID THIRD AND FOURTH EDGES OF THE TABLE STRUCTURE, AND MEANS AT SAID THIRD AND FOURTH EDGES OF SAID TABLE STRUCTURE FOR BENDING SAID THIRD AND FOURTH MARGINS OF THE BLANK IN SAID SECOND POSITION IN THE OPPOSITE DIRECTION TO FORM THE THIRD AND FOURTH HOOKS, THE MEANS FOR BENDING THE FIRST AND SECOND MARGINS OF THE BLANK COMPRISING FIRST AND SECOND VERTICALLY MOVABLY CLAMPING BARS EACH CARRYING A BENDING BLADE ADAPTED TO CLAMP THE BLANK TO THE TABLE STRUCTURE, AND FIRST AND SECOND BENDING BARS MOUNTED FOR MOVEMENT TO BEND THE FIRST AND SECOND MARGINS OF THE BLANK UP AND AROUND THE EDGES OF SAID BENDING BLADES AND OVER THE LATTER, THE MEANS FOR BENDING THE THIRD MARGIN OF THE BLANK COMPRISING A THIRD VERTICALLY MOVABLE BAR CARRYING YIELDING PRESSER MEANS FOR CLAMPING THE BLANK TO THE TABLE STRUCTURE AND MEANS FOR BENDING DOWN THE THIRD MARGIN OF THE BLANK AROUND SAID THIRD EDGE OF THE TABLE, AND A THIRD BENDING BAR ADAPTED TO MOVE IN UNDER SAID THIRD EDGE OF THE TABLE AND BEND IN THE THIRD MARGIN OF THE BLANK, AND THE MEANS FOR BENDING THE FOURTH MARGIN OF THE BLANK COMPRISING A FOURTH VERTICALLY MOVABLE CLAMPING BAR ADAPTED TO CLAMP THE BLANK TO THE TABLE STRUCTURE AND A FOURTH BENDING BAR MOUNTED FOR MOVEMENT OF BEND THE FOURTH MARGIN OF THE BLANK DOWNWARD AROUND THE FOURTH EDGE OF THE TABLE STRUCTURE AND UNDER THE LATTER. 